SABESP Announces Material Fact

SAO PAULO, April 19, 2013 /PRNewswire/ -- Companhia de Saneamento Basico do Estado de Sao Paulo - SABESP (BM&FBovespa: SBSP3; NYSE: SBS), one of the largest water and sewage service providers in the world based on the number of customers, pursuant to Instruction 358 issued by the Brazilian Securities and Exchange Commission (CVM) on January 3, 2002, as amended, hereby informs its shareholders and the market in general that the Company's Board of Directors approved on this date a tariff adjustment of 2.3509%, in compliance with ARSESP Resolution 406 and Article 28 of the Tariff System Regulation approved by State Decree no. 41446, dated December 16, 1996.

The Company also announces the following:

a)

The Regulation and Supervision Rate of 0.5% approved by Resolution 406 will be applied immediately after the conclusion of the operational adjustments necessary for the inclusion of this rate in the bills in the municipalities where it will be charged.

b)

On April 4, 2013, filed a Request for Reconsideration at ARSESP, related to the terms of Resolution 406, with the objective of protecting the Company's interests within the ongoing Tariff Review process.

The full version of the Request for Reconsideration is available in the Investor Relations section of Sabesp's website.

c)

On this date, ARSESP informed the Company that its Executive Board approved Resolution 413, which envisages the cancellation of the validity of Resolution 407, postponing authorization for the pass-through to the service bill of the municipal charges provided for by law that must be included in the Tariff Review upon disclosure of the final result of Sabesp's Tariff Review, in compliance with the Program Agreements and the Agreements for the Provision of Water Supply and Sewage Services.

The full version of ARSESP Resolution 413 is available in the Investor Relations section of Sabesp's website.